When first met in the game, Horance was an evil liche working on building his army of undead.

Before Avatar again arrived to Britannia (somewhere in the 200-year period between Ultima VI and VII), Horance of Skara Brae first gained fame as a gifted mage, known most of all for his magical research but also of his great skills of poetry. Then, at some point, he began to turn more and more evil: his poetry turned ill, his shows of magical might turned more dangerous and violent. Then, he got more and more reclusive, and started to study the most dark of the magical arts. He constructed the Dark Tower out of blackrock to the northwestern corner of the isle of Skara Brae, away of the city proper.

In the very center of the tower was the Well of Souls, a powerful magical-spiritual artifact that empowered the lich with terrifying magics that allowed him to raise dead at will and control the undead. As seen in the game, it also affected the restless ghosts. Each night, the spirits of the city - completely unwillingly and not remembering anything specific in the morning - gathered to the Dark Tower to a Black Service, adding to the Liche's power through the Well.

In effort to stop Horance, the townspeople decided to act. Healer Mordra and alchemist Caine came up with a plan. Mordra invented a formula for a magical solution that would dissolve the Liche - a potion of invisibility, a dose of curing potion, and a vial of essence of mandrake. Caine produced the mix according to the instructions given to him. Unfortunately, mayor Forsythe, who relayed the formula from Mordra to Caine, remembered the formula wrong - instead of one part of mandrake, he said the potion needed tons of it. When Caine was mixing the potion, it suddenly exploded in a gigantic fireball. Everyone in the town died either in the explosion or the following fires. Presumably, Horance himself had already became a liche at this point and was not harmed by this explosion, or he became a liche during this event.

Apart of being bound to come to the Black Service, the remaining inhabitants of the city assumed more or less the same kind of life as before - of course, only existing as either undead creatures or ghosts, their lifes were filled with additional grief and sorrows. The most tragic of these tales was that of Caine: He remained in his laboratory, constantly burned by thousands of flames (at least in his mind), blaming the deaths of everyone in the city on him alone. Caine was then also known as "the Tormented One". Outsiders started to avoid the ruins of the city due to all of the undead horrors controlled by Horance.

Much later, The Avatar was asked by the Wisps to find the notebook of Alagner. Alagner was very cooperative, but said that before he could borrow his notebook to the Avatar, he would need to know the answers to the question of Life and Death, which only the Tormented One knows.

Understandably, Caine seized the opportunity to ask the Avatar to free the spirits of the town from Horance's grip. Horance now styled himself as Lord Horance, the future ruler of all Britannia.

Upon first meeting Horance, the Avatar learned Lord Horance's plans: To conquer Britannia with his undead army. Horance had also taken the spirit of Rowena, blacksmith Trent's wife, to his service. He had rendered her mind blank and servile, making her his Queen.

With help from Mordra, Trent, Rowena and Caine, the Avatar was able to produce the correct mixture to destroy Liche. Also needed was a Soul Cage, which Trent built with the Avatar's help, and which the Avatar imbued with the power of the Well of the Souls.

With the Cage and the mixture, the Liche's soul was trapped in the soul cage and destroyed. Horance then awakened a new man - or spirit, no longer evil or especially interested in world conquest, and quite helpful to the Avatar.

As his first task, he asked the Avatar to destroy the Well of Souls, which all spirits were still bound to. Specifically, he needed to find a volunteering ghost to jump in it. Finally, when other souls of the town had been interviewed, only one could be found who could do it: mayor Forsythe. Reluctantly, Forsythe agreed to help, and jumped into the well, thus destroying it. Caine was then happy to tell the Avatar the answers to the question of Life and Death: There are no answers, only questions.

And then, a quote from Horance himself, which I didn't add to the original Wikipedia bit - but it is, in my opinion, one of the greatest lines from any villain in any CRPG:

"Dost thou have any idea of the number of dead people and creatures there are? I thought not. The dead of the ages are mine to summon and control. The graves of beloved ancestors will spew forth their contents into an army. A special treat for the living, mine undead monsters will be. Imagine a skeletal dragon that cannot be killed. Consider a cabal of everliving mages eternally enthralled to me. And the most beautiful part of my plot is that, as the living die in these battles, and they will die, they will swell the ranks of the undead host. I will rule supreme - a world of the dead!"

Something I quietly wonder - is this yet another subtle reference to the evil influence of Electronic Arts? Origin and many other companies are now just zombies in EA's leash...